I. Field of the Invention
The present invention relates to aqueous compositions capable of removing stains from fabrics and carpets. Specifically, the present invention relates to aqueous compositions for removing water and protein stains from fabrics and carpets. Such compositions contain one or more peroxygen compounds and at least one surfactant. More specifically, the present invention relates to such compositions that exhibit superior solution stability and reduced turbidity.
II. Description of the Prior Art
Fabric and carpet fibers easily stain upon contact with water and proteinaceous materials. Such stains are conventionally removed by compositions containing combinations of cleansing surfactants that lift and remove water and protein stains from the fabric. Stain remover compositions may also be formulated to further contain an active oxygen-containing compound (more commonly referred to as a peroxygen compound), such as hydrogen peroxide. Peroxygen compounds oxidize and decolorize stains formed by contact with water and proteinaceous materials.
Fabric cleaning compositions also commonly contain one or more anti-resoiling agents, commonly referred to as soil resists. Soil resists prevent or impede the resoiling of the fabric after cleaning. One type of soil resist, an olefinic/acrylate polymer, is described in U.S. Pat. No. 5,534,167 to Billman. See also U.S. Pat. No. 5,001,004 to Fitzgerald et al. In surfactant-containing cleaning compositions, a polymeric or copolymeric soil resist embrittles the surfactants upon drying. Embrittlement prevents the surfactants from drying into a waxy, tacky layer that remains on the fabric after removal of the cleaning composition. If left on the fabric, such a waxy, tacky layer will attract and hold dirt on the surface of the cleaned fabric.
In addition to providing acceptable stain removal ability, stain removal compositions must be storage stable. A stain removal product may be stored by the ultimate consumer for many months before use under less than ideal conditions. During storage, the components of the composition cannot separate from each other if the composition is to remain fully effective. Furthermore, the composition cannot become turbid as a turbid product is not acceptable to the consumer. The problem of compositional instability is further exacerbated when a peroxygen compound is employed. Peroxygen compounds easily degrade and the decolorizing ability of a peroxygen compound is quickly lost upon degradation. Furthermore, degradation of a peroxygen compound generates gases that can cause swelling of the package in which the stain removing composition is provided.